Hey Chris, how have you been!?
The velocity pumps are going to be te quietest out there, however you do have to deal with the heat from them. You might consider looking at the Red Dragon Mini 25M3 or 35M3 as well. You can run them either submersible or external, however they are designed more to be circulation pumps rather than pressure rated pumps. They are extremely durable, and run pretty darn quiet to boot. The last one to take a look at would be either the PanWorld 40PX or 50PX. You are going to get the most noise of the three I recommended with this one, however it is still fairly quiet. I run one at home, and have been happy with it for a few years now.
Thanks,
Jeremy